U.S. Department of Energy Office of Biological and Environmental Research

BER Research Highlights

Evaluation of Cloud Properties and Precipitation for Stratiform and Convective Simulations
Published: April 23, 2012
Posted: February 14, 2013

U.S. Department of Energy (DOE) researchers continue to test the performance of model cloud microphysics, or the way droplets and ice crystals form, evolve, and precipitate in models. Microphysics parameters influence cloud evolution and climate conditions and the complex schemes require extensive and ongoing testing against observations. Simulations of frontal stratiform precipitation events are sensitive to the representation of snow in the cloud microphysics parameterization, while convective precipitation events are mainly sensitive to the representation of the largest rimed (ice-coated) ice species, either graupel (cold ice-water condensed on a snow crystal) or hail (ball of dense layered ice). DOE scientists at Brookhaven National Laboratory and their collaborators performed model microphysics sensitivity experiments of the representation of snow and rimed ice species for two composites of 15 stratiform and 15 convective observed precipitation events. Cloud properties and surface precipitation characteristics of all events were rigorously evaluated against satellite- and radar-derived observations. Simulations that include graupel and a temperature-dependent snow parameter during both convective and stratiform events yielded results that consistently agreed better with satellite observations. The enhanced ice depositional growth rates in these experiments led to significantly improved cloud-top heights. Compared to previous model experiments, surface precipitation was less sensitive to whether graupel or hail was chosen as the rimed ice species. However, capturing peak precipitation rates required including graupel in the microphysics scheme. This study used precipitation and cloud observations to constrain and improve the requirements for cloud microphysical schemes for both convective and stratiform cloud modeling.

Reference: Van Weverberg, K., N. van Lipzig, L. Delobbe, and A. Vogelmann. 2012: "The Role of Precipitation Size Distributions in Km-Scale NWP Simulations of Intense Precipitation: Evaluation of Cloud Properties and Surface Precipitation," Quarterly Journal of the Royal Meteorological Society 138, 2163-81. DOI: DOI:10.1002/qj.1933. (Reference link)

Contact: Dorothy Koch, SC-23.1, (301) 903-0105, Ashley Williamson, SC-23.1, (301) 903-3120
Topic Areas:

  • Research Area: Earth and Environmental Systems Modeling
  • Research Area: Atmospheric System Research

Division: SC-23.1 Climate and Environmental Sciences Division, BER


BER supports basic research and scientific user facilities to advance DOE missions in energy and environment. More about BER

Recent Highlights

May 10, 2019
Quantifying Decision Uncertainty in Water Management via a Coupled Agent-Based Model
Considering risk perception can improve the representation of human decision-making processes in age [more...]

May 09, 2019
Projecting Global Urban Area Growth Through 2100 Based on Historical Time Series Data and Future Scenarios
Study provides country-specific urban area growth models and the first dataset on country-level urba [more...]

May 05, 2019
Calibrating Building Energy Demand Models to Refine Long-Term Energy Planning
A new, flexible calibration approach improved model accuracy in capturing year-to-year changes in bu [more...]

May 03, 2019
Calibration and Uncertainty Analysis of Demeter for Better Downscaling of Global Land Use and Land Cover Projections
Researchers improved the Demeter model’s performance by calibrating key parameters and establi [more...]

Apr 22, 2019
Representation of U.S. Warm Temperature Extremes in Global Climate Model Ensembles
Representation of warm temperature events varies considerably among global climate models, which has [more...]

List all highlights (possible long download time)